Rule



Feb. 9, 1937. F. o. CARLSON RULE Filed March 18, 1935 IVENTOR. cK 0Carlson ATTORNEY.

Patented Feb. 9, 1937 UNITED STATES PATE T QFFICE Master RuleManufacturing Company,

Inc., New York, N. Y., a corporation of New York Application March 18,

3 Claims.

This invention relates broadly to space measuring instruments of theruler type and more particularly of the folding rule type.

One of the objects of this invention is to provide exceedingly simpleattachments to be applied to a graduated rule to increase its field ofusefulness by adapting it to calipering.

A further object of this invention is to provide graduated metalterminal sections for a 10 folding rule to protect it against wear andabuse.

A still further object of this invention is to provide such a metal endsection folding rule with simple attachments to adapt it to calipermg.

These and other objects, as will appear from the following disclosureare secured by means of this invention.

This invention resides substantially in the combination, construction,arrangement and relative location of parts, all as will be described indetail below.

In the drawing,

Fig. 1 is a plan View of a folding rule in accordance with thisinvention with one section partly broken away, and showing the rulepartly extended;

Fig. 2 is a side elevational view thereof showing the rule folded;

Fig. 3 is an enlarged plan view of a portion of one end section with thecalipering attachments applied;

Fig. 4 is a cross sectional view taken on the line ll-li of Fig. 1.

As illustrated in the drawing, the rule consists of a plurality ofindividual graduated sections l, which are pivotally connected togetherto form an expansible rule which may be readily folded. In a generalsense rules of this type are old and well known in the art in manyforms, 40 and for this reason the structure of the rule has not beenshown in detail. Likewise the joints which pivotally connect the rulesections together are old and well known in many forms, and hence haveonly been shown diagrammatically.

The basic feature of this invention consists in the application ofsimple attachments to one of the end sections 2 of the rule to adapt itfor calipering measurements. One of these attachments consists of th'emetal piece 3 pivotally mounted at 6 on the end of the end section sothat it may be bent out to the position shown in Fig. 3. The otherattachment consists of a metal slide 4 having channeled edges, as isclear from Fig. 4, so that it may be slidably mounted upon the endsection 2. This slide carries a pivotally mounted arm which may be swungto the position shown in Fig. 1 and moved out to the position shown inFig. 3 for use in conjunction with the projecting end 8 of the "5.pivoted attachment 3.

Folding rules of this type are commonly made of wood, moldedcompositions, and the like. The use of the slide 4 on the end section ofa rule made of such materials would have a tendency 10 to wear itunduly, causing the slide to ultimately slip, and marring thegraduations which are usually stamped or painted thereon. Thesedifficulties were solved in accordance with this invention by making thetwo end sections of a suitl5 able metal such as steel, aluminum, and thelike. Since the end sections of a folding rule are quite frequently usedin taking short measurements, the construction of the end sections ofmetal is of distinct advantage in view ofthe greater accuracy with whichthey may be graduated, and the greater ease with which they may be used.

In addition the metal end sections resist wear of the slide, insuring itagainst slipping, and being graduated by directly marking the metal,these gi'aduations are not worn o or obscured by repeated movements ofthe slide. A final advantage of the metal end sections on a folding rulehaving wooden sections is that the wooden sections are substantiallymetal encased, protecting them against wear incident to use andtransportation. As is well known, the ordinary wooden section foldingrule when carried about in the pocket or tool case of the user quicklywears at the ends, obscuring the graduations thereon and reducing itsusefulness. By making the two outside or end sections 2 of metal therule is substantially protected against wear, as will be apparent fromFig. 2.

Referring to the details, it will be seen that the corner 'l of the endsection 2 which supports the calipering attachments is rounded so thatthe pivoted member 3 can be swung between the two positions asillustrated in Figs. 1 and 3.

The slide Il, which is preferably made of a strong metal, istransversely curved, as is clear from Fig. 4. It is so proportioned thatits flanges grip the edges of the end section 2 and frequently hold itagainst movement. However, when pressure is applied to the slide to moveit in either direction the outwardly bowed portion of the slide ispressed inwardly, causing the flanges to loosen their grip on the sidesof the end section upon which they are mounted.

'Ihe slide then moves freely and as soon as 55 the pressure is removedit again grips the section to hold it in place. Pivotally connected at 9on the slide is an arm or finger 5, which is provided with a small bossor projection I2 which cooperates with a properly positioned depressionH in the slide body so as to lock the finger in the position shown inFig. 1. To lock the finger in its extended position as shown in Fig. 3the slide is notched at its edge at I so that the boss I2 Will snaptherein and hold the finger at right angles to the rule section. Withthe parts in the position as shown in Fig. 3 it Will be readily apparentthat calipering measurements can be easily taken either with the endsection folded outwardly from the rest of the rule, or even when therule is entirely closed. The active edge of the attachment 3 is in lineWith the end of the rule so that any distance d, representing theoutside diameter of a shaft, for example, is directly read from the ruleas will be apparent from Fig. 3 by noting the position of the linger 5with respect to the graduations on the rule section. Thus the distancedis 1%" as illustrated in Fig. 3.

As an added convenience the attachment 3 is graduated along one edge sothat short measurements can be taken on it in the position shown in Fig.3. These graduations are standard so that When the attachment 3 is inthe position in Fig. 1 the graduations thereon lie directly over thecorresponding graduations of the first inch on the section 2.

From the above description it will be apparent that the objects of thisinvention are simply attained by means of a structure which may beillustrated by those skilled in the art Without departure from the scopeof the invention. I do not, therefore, desire to be strictly limited tothe disclosure as given for purposes of illustration, but rather to thescope of the appended claims.

What I seek to secure by United States Letters Patent is:

1. A folding rule as described comprising a plurality of graduatedstrips of Wood pivotally connected together at respective ends to forman articulated rule, and a pair of metal graduated terminal sectionspivotally connected to the free ends of the Wooden sections.

2. A rule as described comprising a plurality of graduated non-metallicsections connected together so as to be movable into the full rulelength and closed into overlying sections, and a metal end sectionmovably connected to one of the non-metallic sections to form a terminalsection.

8. A folding rule as described comprising a plurality of graduatednon-metallic sections pivotally connected together at respective ends,and a metal end section pivotally secured to one of the non-metallic endsections to form a terminal section.

FREDERICK o. CARLSON.

